Determination of sulfur isotope ratio of sulfate in mountainous streams on Yakushima Island after in-situ collection/concentration of sulfate

Researchers found that sulfur isotope ratios (δ³⁴S) in non-seasalt sulfate (nss δ³⁴S) on Yakushima Island vary significantly by region, with higher values (+1.1 to +7.5‰) in the western and mountainous areas compared to the northeastern region (-3.9 to +0.3‰). This suggests that sulfur-bearing air masses from coal combustion in Asia, characterized by high δ³⁴S values, are transported westward and deposited on the island's higher elevations, such as Miyanoura-dake (1936 m). The study employed a novel in-situ collection method using anion exchange resin in mesh bags to efficiently gather sulfate for analysis, making it suitable for remote or mountainous research settings where sample transport is challenging. This approach addresses practical limitations while providing insights into the origin and distribution of atmospheric sulfur pollutants affecting freshwater ecosystems.

DOI, T., NAGAFUCHI, O., YOKOTA, K., YOSHIMURA, K., AKUNE, S., YAMANAKA, T., & MIYABE, S. (2011). Determination of sulfur isotope ratio of sulfate in mountainous streams on Yakushima Island after in-situ collection/concentration of sulfate. Japanese Journal of Limnology (Rikusuigaku Zasshi), 72(2), 135–144. https://doi.org/10.3739/rikusui.72.135